import java.io.File;

import com.googlecode.javacpp.Loader;
import com.googlecode.javacv.*;
import com.googlecode.javacv.cpp.*;
import static com.googlecode.javacv.cpp.opencv_core.*;
import static com.googlecode.javacv.cpp.opencv_imgproc.*;
import static com.googlecode.javacv.cpp.opencv_calib3d.*;
import static com.googlecode.javacv.cpp.opencv_objdetect.*;

public class Demo {
    public static void main(String[] args) throws Exception {
//        String classifierName = null;
//        if (args.length > 0) {
//            classifierName = args[0];
//        } else {
//            System.err.println("Please provide the path to \"haarcascade_frontalface_alt.xml\".");
//            System.exit(1);
//        }
    	String classifierName = "haarcascade_eye_tree_eyeglasses.xml";
    	
    	   File imageFile = new File(classifierName);
           if(!imageFile.exists()) {
                   throw new RuntimeException("Image file " + classifierName + " not found.");
           }
    	
        // Preload the opencv_objdetect module to work around a known bug.
        Loader.load(opencv_objdetect.class);

        // We can "cast" Pointer objects by instantiating a new object of the desired class.
        CvHaarClassifierCascade classifier = new CvHaarClassifierCascade(cvLoad(classifierName));
        if (classifier.isNull()) {
            System.err.println("Error loading classifier file \"" + classifierName + "\".");
            System.exit(1);
        }

        // CanvasFrame is a JFrame containing a Canvas component, which is hardware accelerated.  
        // It can also switch into full-screen mode when called with a screenNumber.
        CanvasFrame frame = new CanvasFrame("Some Title");

        // OpenCVFrameGrabber uses opencv_highgui, but other more versatile FrameGrabbers 
        // include DC1394FrameGrabber, FlyCaptureFrameGrabber, and FFmpegFrameGrabber.
        FrameGrabber grabber = new OpenCVFrameGrabber(0);
        grabber.start();

        // FAQ about IplImage:
        // - For custom raw processing of data, getByteBuffer() returns an NIO direct
        //   buffer wrapped around the memory pointed by imageData.
        // - To get a BufferedImage from an IplImage, you may call getBufferedImage().
        // - The createFrom() factory method can construct an IplImage from a BufferedImage.
        // - There are also a few copy*() methods for BufferedImage<->IplImage data transfers.
        IplImage grabbedImage = grabber.grab();
        int width  = grabbedImage.width();
        int height = grabbedImage.height();
        IplImage grayImage    = IplImage.create(width, height, IPL_DEPTH_8U, 1);
        IplImage rotatedImage = grabbedImage.clone();

        // Let's create some random 3D rotation...
        CvMat randomR = CvMat.create(3, 3), randomAxis = CvMat.create(3, 1);
        // We can easily and efficiently access the elements of CvMat objects
        // with the set of get() and put() methods.
        randomAxis.put((Math.random()-0.5)/4, (Math.random()-0.5)/4, (Math.random()-0.5)/4);
        cvRodrigues2(randomAxis, randomR, null);
        double f = (width + height)/2.0;        randomR.put(0, 2, randomR.get(0, 2)*f);
                                                randomR.put(1, 2, randomR.get(1, 2)*f);
        randomR.put(2, 0, randomR.get(2, 0)/f); randomR.put(2, 1, randomR.get(2, 1)/f);
        System.out.println(randomR);

        // Objects allocated with a create*() or clone() factory method are automatically released
        // by the garbage collector, but may still be explicitly released by calling release().
        CvMemStorage storage = CvMemStorage.create();

        // We can allocate native arrays using constructors taking an integer as argument.
        CvPoint hatPoints = new CvPoint(3);

        // Again, FFmpegFrameRecorder also exists as a more versatile alternative.
        FrameRecorder recorder = new OpenCVFrameRecorder("output.avi", width, height);
        recorder.start();

        while (frame.isVisible() && (grabbedImage = grabber.grab()) != null) {
            // Let's try to detect some faces! but we need a grayscale image...
            cvCvtColor(grabbedImage, grayImage, CV_BGR2GRAY);
            CvSeq faces = cvHaarDetectObjects(grayImage, classifier, storage, 
                1.1, 3, CV_HAAR_DO_CANNY_PRUNING);
            int total = faces.total();
            for (int i = 0; i < total; i++) {
                CvRect r = new CvRect(cvGetSeqElem(faces, i));
                int x = r.x(), y = r.y(), w = r.width(), h = r.height();
                cvRectangle(grabbedImage, cvPoint(x, y), cvPoint(x+w, y+h), CvScalar.RED, 1, CV_AA, 0);

                // To access the elements of a native array, use the position() method.
                hatPoints.position(0).x(x-w/10)   .y(y-h/10);
                hatPoints.position(1).x(x+w*11/10).y(y-h/10);
                hatPoints.position(2).x(x+w/2)    .y(y-h/2);
                cvFillConvexPoly(grabbedImage, hatPoints.position(0), 3, CvScalar.GREEN, CV_AA, 0);
            }

            // Let's find some contours! but first some thresholding...
            cvThreshold(grayImage, grayImage, 64, 255, CV_THRESH_BINARY);

            // To check if an output argument is null we may call either isNull() or equals(null).
            CvSeq contour = new CvSeq(null);
            cvFindContours(grayImage, storage, contour, Loader.sizeof(CvContour.class),
                    CV_RETR_LIST, CV_CHAIN_APPROX_SIMPLE);
            while (contour != null && !contour.isNull()) {
                if (contour.elem_size() > 0) {
                    CvSeq points = cvApproxPoly(contour, Loader.sizeof(CvContour.class),
                            storage, CV_POLY_APPROX_DP, cvContourPerimeter(contour)*0.02, 0);
                    cvDrawContours(grabbedImage, points, CvScalar.BLUE, CvScalar.BLUE, -1, 1, CV_AA);
                }
                contour = contour.h_next();
            }

            cvWarpPerspective(grabbedImage, rotatedImage, randomR);

            frame.showImage(rotatedImage);
            recorder.record(rotatedImage);

            cvClearMemStorage(storage);
        }
        recorder.stop();
        grabber.stop();
        frame.dispose();
    }
}